In Sept 2016, HDMI spec group defined a HDMI 1.4 capable standard to use USB Type-C without an adapter. This means a PC with Type-C could connect to a Monitor/TV with Type-C. Both sides would require the right software and hardware to make it work.

The smaller Type-C form factor is everywhere. This eliminates the need for an HDMI connector. (Which may or may not remove the need to pay an HDMI royalty if an HDMI royalty… Ask your lawyer, I’m not a lawyer). It would remove the need for devices to have a separate HDMI port.

This increases the complexity of the hardware implementation on the controller and PHY. It needs to be tested to make sure it works. The trade-off to using HDMI 1.4 is the user can’t get the highest HDMI 2.0 and 2.1 features and resolutions.

The question is will monitors appear that natively support HDMI alternate mode. Those monitors might support multiple inputs including

VGA (may be eliminated)

DVI (may be eliminated)

DisplayPort

DisplayPort Alternate Mode for Type-C

HDMI

HDMI Alternate Mode for Type-C

USB (a la DisplayLink’s awesome technology)

USB using an updated Audio Video Class for native streaming (not holding a lot of hope for this)

I would like to note, I myself am a huge fan of DisplayLink’s USB video technology because it’s been around for years, and it works super well, and is supported on Windows, Mac, and Android systems. It’s a great example of a private system that works well and is economical. We have a USB only input, portable monitor in the lab.

There is definitely a future with HDMI over USB Type-C. For now, the HDMI Forum is pushing adapter “dongles” or short cables with chips inside. This actually converts from a USB data stream into HDMI. Again this is supported by DisplayLink and several other companies. Here’s an example.

I’ve stolen the paragraph directly from HDMI Wikipedia for those that like more detail.

“HDMI Alternate Mode for USB Type-C

The HDMI Alternate Mode for USB-C allows HDMI-enabled sources with a USB-C connector to directly connect to standard HDMI display devices, without requiring an adapter.[174] The standard was released in September 2016, and supports all HDMI 1.4b features such as video resolutions up to 4K Ultra HD 30 Hz, and Consumer Electronic Control (CEC).[175] Previously, the similar DisplayPortAlternate Mode could be used to connect to HDMI displays from USB Type-C sources, but where in that case, active adapters were required to convert from DisplayPort to HDMI, HDMI Alternate Mode connects to the display natively.[176]

The Alternate Mode reconfigures the four SuperSpeed differential pairs present in USB-C to carry the three HDMI TMDS channels and the clock signal. The two Sideband Use pins (SBU1 and SBU2) are used to carry the HDMI Ethernet and Audio Return Channel and the Hot Plug Detect functionality (HEAC+/Utility pin and HEAC−/HPD pin). As there are not enough reconfigurable pins remaining in USB-C to accommodate the DDC clock (SCL), DDC data (SDA), and CEC – these three signals are bridged between the HDMI source and sink via the USB Power Delivery 2.0 (USB-PD) protocol, and are carried over the USB-C Configuration Channel (CC) wire.[174] This is possible because the cable is electronically marked (i.e., it contains a USB-PD node) that serves to tunnel the DDC and CEC from the source over the Configuration Channel to the node in the cable, these USB-PD messages are received and relayed to the HDMI sink as regenerated DDC (SCL and SDA signals), or CEC signals.[174]”

Eric started working on USB in 1995, starting with the world’s first BIOS that supported USB Keyboards and Mice while at Award Software. After a departure into embedded systems software for real-time operating systems, he returned to USB IP cores and software at inSilicon, one of the leading suppliers of USB IP. In 2002, inSilicon was acquired by Synopsys and he’s been here since. He also served as Chairman of the USB On-The-Go Working Group for the USB Implementers Forum from 2004-2006.

Eric received an M.B.A. from Santa Clara University and an M.S. in Engineering from University of California Irvine, and a B.S. in Engineering from the University of Minnesota. and is a licensed Professional Engineer in Civil Engineering in the State of California.